A low-complexity compression algorithm for hyperspectral images based on distributed source coding (DSC) is proposed in this paper. The proposed distributed compression algorithm can realize both lossless and lossy co...
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A low-complexity compression algorithm for hyperspectral images based on distributed source coding (DSC) is proposed in this paper. The proposed distributed compression algorithm can realize both lossless and lossy compression, which is implemented by performing scalar quantization strategy on the original hyperspectral images followed by distributed lossless compression. Multilinear regression model is introduced for distributed lossless compression in order to improve the quality of side information. Optimal quantized step is determined according to the restriction of the correct DSC decoding, which makes the proposed algorithm achieve near lossless compression. Moreover, an effective rate distortion algorithm is introduced for the proposed algorithm to achieve low bit rate. Experimental results show that the compression performance of the proposed algorithm is competitive with that of the state-of-the-art compression algorithms for hyperspectral images.
An accurate and efficient finite-difference method for solving the incompressible Navier-Stokes equations on curvilinear grids is developed. This method combines the favorable features of the staggered grid and semist...
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An accurate and efficient finite-difference method for solving the incompressible Navier-Stokes equations on curvilinear grids is developed. This method combines the favorable features of the staggered grid and semistaggered grid approaches. All components of velocity are stored at the corner vertices, and pressure is stored at the grid cell centers. All components of the momentum equations are discretized at cell vertices, facilitating a consistent discretization of the diffusive and convective terms as the boundaries are approached. The Christoffel symbol does not appear in the transformed equations and the cost of computation is comparable to that of the staggered-grid approach. A projection method is used to effectively evolve the discrete system in time, while ensuring a divergence-free velocity field. The discrete divergence and gradient operators of the projection step are constructed on a staggered gird layout leading to exact satisfaction of the discrete continuity. The solution of the Poisson-Neumann equation in the projection step is free of any spurious eigenmodes. The validity of the method is demonstrated on four benchmark problems. The Taylor-Green vortex problem is solved on a curvilinear grid with highly skewed cells and a second-order convergence in l-norm is observed. The mixed convection in a lid-driven cavity is solved on a highly curvilinear grid and excellent agreement with literature is obtained. The results for flow past a cylinder and pusatile flow in a 90 degrees bend are compared with the existing experimental data in the literature. The predictions agree well with the measured data, and validate the approach used.
We note that the seal can function stably in the fluid friction mode (for thechosen design characteristics of the seal unit) when the axial rigidity of the lifting layer at thecontact of the parr of surfaces of the fa...
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We note that the seal can function stably in the fluid friction mode (for thechosen design characteristics of the seal unit) when the axial rigidity of the lifting layer at thecontact of the parr of surfaces of the face seal ring pair is high. That rigidity is the parameterfor optimizing a seal with a wedge-shaped slot. When designing the unit, the designer must strive tocreate a face seal with the highest attainable lifting layer rigidity in the contact of the facesurfaces of the ring pair.
The performance descending of current congested link inference algorithms is obviously in dynamic routing IP network, such as the most classical algorithm CLINK. To overcome this problem, based on the assumptions of M...
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The performance descending of current congested link inference algorithms is obviously in dynamic routing IP network, such as the most classical algorithm CLINK. To overcome this problem, based on the assumptions of Markov property and time homogeneity, we build a kind of Variable Structure Discrete Dynamic Bayesian (VSDDB) network simplified model of dynamic routing IP network. Under the simplified VSDDB model, based on the Bayesian Maximum A Posteriori (BMAP) and Rest Bayesian Network Model (RBNM), we proposed an Improved CLINK (ICLINK) algorithm. Considering the concurrent phenomenon of multiple link congestion usually happens, we also proposed algorithm CLILRS (Congested Link Inference algorithm based on Lagrangian Relaxation Subgradient) to infer the set of congested links. We validated our results by the experiments of analogy, simulation, and actual Internet.
The reproducing kernel algorithm is described in order to obtain the efficient analytical-numerical solutions to nonlinear systems of two point, second-order periodic boundary value problems with finitely many singula...
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The reproducing kernel algorithm is described in order to obtain the efficient analytical-numerical solutions to nonlinear systems of two point, second-order periodic boundary value problems with finitely many singularities. The analytical-numerical solutions are obtained in the form of an infinite convergent series for appropriate periodic boundary conditions in the space W-2(3)[0, 1], whilst two smooth reproducing kernel functions are used throughout the evolution of the algorithm to obtain the required nodal values. An efficient computational algorithm is provided to guarantee the procedure and to confirm the performance of the proposed approach. The main characteristic feature of the utilized algorithm is that the global approximation can be established on the whole solution domain, in contrast with other numerical methods like onestep and multistep methods, and the convergence is uniform. Two numerical experiments are carried out to verify the mathematical results, whereas the theoretical statements for the solutions are supported by the results of numerical experiments. Our results reveal that the present algorithm is a very effective and straightforward way of formulating the analytical-numerical solutions for such nonlinear periodic singular systems.
Symbolic languages are increasingly being used in the analysis and implementation of control algorithms. Many of these control procedures involve some type of differentiation or Jacobian formulation. Automatic differe...
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Symbolic languages are increasingly being used in the analysis and implementation of control algorithms. Many of these control procedures involve some type of differentiation or Jacobian formulation. Automatic differentiation provides an alternative means of computing this information which is rarely considered in the control literature. This correspondence will discuss the use of automatic differentiation. Numerical results comparing the use of automatic differentiation and symbolic approaches in the context of a particular nonlinear control system will be given.
Novel dual band-notched monopole antenna is proposed in this paper, which is designed by an improved particle swarm optimization algorithm linked with IIFSS. By etching a one order Minkowski fractal slot on the radiat...
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Novel dual band-notched monopole antenna is proposed in this paper, which is designed by an improved particle swarm optimization algorithm linked with IIFSS. By etching a one order Minkowski fractal slot on the radiating patch and introducing a semioctagon-shaped resonator on the back plane, excellent dual notched frequency bands characteristics of the proposed antenna are achieved. The antenna satisfies the VSWR requirement of less than 2.0 in the frequency band between 2.87 and 12 GHz, except two frequency stop-bands of 3.2-4.01 GHz and 5.55-6.1 GHz. The effects of the key parameters on the dual notched bands are also analyzed. A fairly stable radiation pattern over the frequency range of interest can be obtained. Moreover, measured group delay and transmission characteristics indicate that the antenna has good pulse handling capabilities.
Observing that many visual effects (depth-of-field, motion blur, soft shadows, spectral effects) and several sampling modalities (time, stereo or light fields) can be expressed as a sum of many pinhole camera images, ...
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Observing that many visual effects (depth-of-field, motion blur, soft shadows, spectral effects) and several sampling modalities (time, stereo or light fields) can be expressed as a sum of many pinhole camera images, we suggest a novel efficient image synthesis framework that exploits coherency among those images. We introduce the notion of distribution flow that represents the 2D image deformation in response to changes in the high-dimensional time-, lens-, area light-, spectral-, etc. coordinates. Our approach plans the optimal traversal of the distribution space of all required pinhole images, such that starting from one representative root image, which is incrementally changed (warped) in a minimal fashion, pixels move at most by one pixel, if at all. The incremental warping allows extremely simple warping code, typically requiring half a millisecond on an Nvidia Geforce GTX 980Ti GPU per pinhole image. We show, how the bounded sampling does introduce very little errors in comparison to re-rendering or a common warping-based solution. Our approach allows efficient previews for arbitrary combinations of distribution effects and imaging modalities with little noise and high visual fidelity.
Modeling and simulation is essential for performance evaluation of wireless systems and specific algorithms used, for instance, during resource allocation. For Current and future wireless systems, several properties h...
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Modeling and simulation is essential for performance evaluation of wireless systems and specific algorithms used, for instance, during resource allocation. For Current and future wireless systems, several properties have to be considered such as data traffic, frequency selective fading channels, and radio resource management. Throughout this article, a new system-level simulator concept is presented for packet switched systems using OFDMA, which is called snapshot-based SLS;and represents a compromise between state-of-the-art static and dynamic SLSs. The proposed methodology only considers short time intervals within the busy hour by their statistics so that RRM and data traffic can be considered, as in dynamic SLS, but with lower computational complexity. In this article a description is given of how the cellular setup and traffic generation are performed for the proposed snapshot concept. Furthermore, a new methodology is proposed for a quality measure of resource units that is applicable to future wireless systems using an interleaved subcarrier allocation. Exemplary simulation results show that the developed concept is able to evaluate the performance of OFDMA systems considering the impact of, for example, data traffic and resource allocation strategies.
A new construction adder based on Chinese abacus algorithm is presented in this paper. There are two kinds of beads used in this construction. Each column element has three higher beads with a weight of four and three...
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A new construction adder based on Chinese abacus algorithm is presented in this paper. There are two kinds of beads used in this construction. Each column element has three higher beads with a weight of four and three lower beads with a weight of one. The proposed 32-bit adder contains eight column elements. The construction was simulated by the technology of TSMC 0.18 mu m CMOS process. Layout was also made by the same technology. The maximum delay of the 32-bit abacus adder is 0.91 ns and 14% less than that of Carry Look-ahead Adders for 0.18 mu m technology. The power consumption of the abacus adder is 3.1 mW and 28% less than that of Carry Look-ahead Adders for 0.18 mu m technology. Recent researches are compared with the proposed adder. The construction was also simulated by Predictive Technology Model. The PTM results also presented. The use of Chinese abacus approach offers a competitive technique with respect to other adders. (C) 2012 Elsevier Ltd. All rights reserved.
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